get_histogram

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are supplied, so the description carries the full burden. It does disclose the return fields and defaults, but says nothing about whether statistics cover the whole layer or the selection, what happens with no active image/layer, or cost on large images.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

One front-loaded purpose sentence followed by compact parameter and return blocks; every line adds information and nothing is padded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With only two optional parameters and no output schema, the description supplies the return shape and default values, which is most of what an agent needs. It falls short only on edge-case behavior (no active layer, selection scope, error responses).

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, and the description compensates well: it enumerates the valid channel values ("value" default, red, green, blue, alpha) and explains image_index as a target image index defaulting to 0, adding real meaning beyond the bare title-typed schema properties.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ("Get histogram statistics") plus scope ("for a channel of the active layer"), which cleanly separates it from siblings like get_image_metadata, get_pixel_color, and get_image_bitmap.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied – an agent can infer this is for analyzing tonal/luminance distribution, but the description never says when to prefer it over get_pixel_color or get_image_metadata, nor any prerequisites such as requiring an open image with an active layer.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.